A conventional X-ray apparatus includes a top board for supporting a subject placed thereon, an X-ray tube for irradiating the subject with X-rays, an X-ray detector, such as a flat panel X-ray detector (FPD), facing the X-ray tube across the top board of a radiographing table for detecting X-rays transmitting through the subject. At least one of the X-ray tube and the X-ray detector is supported on a strut. The strut has a compression unit supported thereon for compressing a site of interest of the subject.
The compression unit includes a compression member for compressing the subject and a compression-unit movement drive. The movement drive moves the compression member in a direction of compressing the subject and in a direction opposite thereto. The subject having taken a barium contrast media is placed on the top board. Then radiography is conducted while the compression unit compresses the site of interest of the subject placed on the top board. See, for example, Patent Literature 1.
The following are disclosed as for an X-ray apparatus provided with a compression unit. See, for example, Patent Literatures 2 through 5. Specifically, an X-ray apparatus includes a radiographing table having a top board for supporting a subject placed thereon, an X-ray irradiation apparatus suspended from a ceiling, and an X-ray imaging device below the radiographing table for taking an X-ray image. The radiographing table of the X-ray apparatus has rails on both side faces thereof for attaching accessories. A compression unit is attached to the rails.    [Patent Literature 1] Japanese Patent Publication No. 2005-353A    [Patent Literature 2] Japanese Patent Publication No. H08-275936A    [Patent Literature 3] Japanese Patent Publication No. H08-275939A    [Patent Literature 4] Japanese Patent Publication No. H08-275941A    [Patent Literature 5] Japanese Patent Publication No. 2004-160263A